The present invention relates to a plastic container for liquids, particularly beverages such as beer.
Most current beer kegs include a steel body with a valve in the top for both filling the keg and for accessing the contents. The steel kegs are reusable. Empty kegs are returned and then washed and refilled in an automated process. The steel kegs are inverted, such that the valve is at the bottom of the keg to facilitate draining during cleaning. The interior of the body of the keg is washed by spraying cleansing liquids through the valve. The cleansing liquids wash the inner surface of the body of the keg and then drain downward through the valve. The kegs are typically then filled in the inverted position through the valve at the bottom of the keg. Throughout the automated process, a cylinder clamps the body of the keg with a high force (between 200 and 300 lb.) to hold the keg in place while the washing and filling heads connect to the valve at the bottom of the keg.
There are several problems with the use of steel kegs. First, they are fairly heavy, even when empty. Second, they are expensive and are not always returned by the user. If a deposit is charged to the user to ensure the return of the keg, this may discourage the user from choosing to purchase beer by the keg in the first place. However, if the deposit is too low, it is possible that the value of the steel in the keg exceeds the amount of the deposit, thus contributing to some kegs not being returned.